Quantum chemical studies and spectroscopic investigations on 22-amino-3-methyl-5-nitropyridine by density functional theory.

Quantum chemical calculations on energy and molecular structure of 2-amino-3-methyl-5-nitropyridine (2A3M5NP) have been attempted by implementing DFT/B3LYP method using 6-311G (d,p), 6-311G++ (d,p) and cc-pVTZ basis sets. The optimized geometry and the vibrational analysis for energetically most stable configuration, are carried out theoretically by using B3LYP/cc-pVTZ basis set. The computed vibrational frequencies were scaled by using scaling factors and compared with the experimental Fourier Transform Infra-Red (FTIR) solid phase spectrum in the region 4000-400 cm-1 and FT-Raman spectrum in the region 4000-100 cm-1. The complete vibrational assignments, analysis and correlation of fundamental modes of the compound have been carried out using the potential energy distribution (PED). The intramolecular charge transfer, hyperconjugative interaction of the compound is investigated from natural bonding orbital (NBO) analysis. The UV-Visible spectrum of 2A3M5NP was obtained with ethanol as a solvent. The electronic properties such as HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccupied Molecular Orbital) energies are determined by B3LYP/cc-pVTZ basis set. The electronic absorption spectrum of the compound was studied from UV-Visible analysis by using time-dependent density functional theory (TD-DFT). The electron density distribution and chemical reactive sites of 2A3M5NP were analyzed from molecular electrostatic potential (MEP) analysis and frontier molecular orbital (FMO) analysis.

Enhanced Expression of FRA16B using AT-Rich DNA Binding Chemicals in a Woman with Secondary Amenorrhoea.

Fragile sites represent regions of chromatin that fail to compact during mitosis. Based on the prevalence and pattern of inheritance they are classified as rare fragile sites or common fragile sites. Rare fragile sites either occur spontaneously or can be induced by certain AT-specific binding chemicals namely distamycin, Hoechst 33258, Berenil and others. The most common of all rare autosomal fragile sites is fra(16)(q22) with a heterozygote frequency of ~5%. FRA16B results from an expansion of a 33 bp AT-rich Minisatellite repeat. These rare forms are usually heritable and segregate in a Mendelian fashion. The proband who was referred for secondary amenorrhoea, revealed 46,XX,fra(16)(q22.1)pat karyotype. Her father and younger sibling were also found to be carriers. This study aimed to delineate the genotypic and phenotypic features exhibited by these carriers and to evaluate FRA16B expression using AT-specific binding chemicals. The additives employed were Berenil, BrdU and Hoechst 33258. Berenil at a concentration of 150 µg/ml showed the highest expression of FRA16B. Although the recent breakthrough in molecular characterization of fragile sites plays a critical role in comprehending their association with various diseases, the physiological link between them and amenorrhoea is not clearly understood.

Removal of elevated level of chromium in groundwater by the fabricated PANI/Fe3O4 nanocomposites.

In this work, we report the reduction of chromium concentration in the polluted groundwater samples from Madurai Kamaraj University area, India, where the dissolved salts in groundwater are reported as serious health hazards for its inhabitants. The water samples have intolerable amounts of total dissolved solids (TDS) and chromium is a prominent pollutant among them. Chromium reduction was achieved by treating the polluted groundwater with PANI/Fe3O4 nanocomposites synthesized by in situ polymerization method. Further experimentation showed that the nanocomposites exhibit better chromium removal characteristics upon increasing the aniline concentration during the synthesis. We were able to reduce chromium concentration in the samples from 0.295 mg L-1 to a tolerable amount of 0.144 mg L-1. This work is expected to open doors for chromium-free groundwater in various regions of India, when improved to an industrial scale.

Evaluation of bone mineral density in thyrotoxicosis.

INTRODUCTION: This project aimed to study the incidence and profile of bone involvement in thyrotoxicosis patients by dual energy X-ray absorptiometry (DEXA) scan and the effect of treatment on the bone mineral density (BMD). METHODS: A total of 50 young patients with a mean age of 29.4 years, diagnosed to have thyrotoxicosis clinically and proven by thyroid function tests, were included in this prospective three-year study conducted at the Madras Medical College and Government General Hospital in Chennai, India. Patients were enrolled if they had bone pain or had elevation of serum alkaline phosphatase. All these patients had a baseline BMD measurement by DEXA scans in the region of the lumbar vertebrae before treatment and the T-score was computed. All other secondary causes of low BMD, like primary hyperparathyroidism, long-term steroid intake, vitamin D deficiency, was ruled out. After definitive management of hyperthyroidism by anti-thyroid drugs and surgery, all the patients with bone involvement had a repeat DEXA scan after one year and the T-score was computed. RESULTS: Out of 50 patients, 46 had bone involvement (92 percent). Based on the World Health Organisation classification, 16 (32 percent) had osteopenia and 30 patients (60 percent) had osteoporosis. After control of thyrotoxicosis, the mean bone mass increased from 0.729 g/sq cm to 0.773 g/sq cm, a statistically significant increase of 0.044 g/sq cm (p-value is less than 0.001) after one year, compared to age- and sex-matched controls. The mean percentage of the bone mass compared to the peak BMD increased from 70.2 percent to 74.2 percent after treatment, an increase of four percent (p-value is less than 0.001). The mean percentage of the bone mass compared to the age-matched BMD increased from 71.2 percent to 75.2 percent after treatment, an increase of four percent (p-value is less than 0.001), all of which were statistically significant. CONCLUSION: Metabolic bone disease should be looked for in all thyrotoxic patients, especially patients complaining of bone pain and those with elevated bone enzymes. DEXA scans offer a convenient, reliable and noninvasive modality for diagnosis and monitoring therapy.